The following invention relates to a laminated ink distribution structure for a printer.
More particularly, though not exclusively, the invention relates to a laminated ink distribution structure and assembly for an A4 pagewidth drop on demand printhead capable of printing up to 1600 dpi photographic quality at up to 160 pages per minute.
The overall design of a printer in which the structure/assembly can be utilized revolves around the use of replaceable printhead modules in an array approximately 8 inches (20 cm) long. An advantage of such a system is the ability to easily remove and replace any defective modules in a printhead array. This would eliminate having to scrap an entire printhead if only one chip is defective.
A printhead module in such a printer can be comprised of a xe2x80x9cMemjetxe2x80x9d chip, being a chip having mounted thereon a vast number of thermo-actuators in micro-mechanics and micro-electromechanical systems (MEMS). Such actuators might be those as disclosed in U.S. Pat. No. 6,044,646 to the present applicant, however, there might be other MEMS print chips.
The printhead, being the environment within which the laminated ink distribution housing of the present invention is to be situated, might typically have six ink chambers and be capable of printing four color process (CMYK) as well as infra-red ink and fixative. An air pump would supply filtered air to the printhead, which could be used to keep foreign particles away from its ink nozzles. The printhead
It is another object of the present invention to provide an ink distribution structure suitable for the pagewidth printhead assembly as broadly described herein.
It is another object of the present invention to provide a laminated ink distribution assembly for a printhead assembly on which there is mounted a plurality of print chips, each comprising a plurality of MEMS printing devices.
It is yet another object of the present invention to provide a method of distributing ink to print chips in a printhead assembly of a printer.
The present invention provides an ink distribution assembly for a printhead to which there is mounted an array of print chips, the assembly serving to distribute different inks from respective ink sources to each said print chip for printing on a sheet, the assembly comprising:
a longitudinal distribution housing having a duct for each said different ink extending longitudinally therealong,
a cover having an ink inlet port corresponding to each said duct for connection to each said ink source and for delivering said ink from each said ink source to a respective one of said ink ducts, and
a laminated ink distribution structure fixed to said distribution housing and distributing ink from said ducts to said print chips.
Preferably the laminated ink distribution structure includes multiple layers situated one upon another with at least one of said layers having a plurality of ink holes therethrough, each ink hole conveying ink from one of said ducts enroute to one of said print chips.
Preferably one or more of said layers includes ink slots therethrough, the slots conveying ink from one or more of said ink holes in an adjacent layer enroute to one of said print chips.
Preferably, the slots are located with ink holes spaced laterally to either side thereof.
Preferably the layers of the laminated structure sequenced from the distribution housing to the array of print chips include fewer and fewer said ink holes.
Preferably one or more of said layers includes recesses in the underside thereof communicating with said holes and transferring ink therefrom transversely between the layers enroute to one of said slots.
Preferably the channels extend from the holes toward an inner portion of the laminated structure over the array of print chips, which inner portion includes said slots.
Preferably each layer of the laminated is a micro-molded plastics layer.
Preferably, the layers are adhered to one another.
Preferably, the slots are parallel with one another.
Preferably, at least two adjacent ones of said layers have an array of aligned air holes therethrough.
The present invention also provides a laminated ink distribution structure for a printhead, the structure comprising:
a number of layers adhered to one another, each layer including a plurality of ink holes formed therethrough, each ink hole having communicating therewith a recess formed in one side of the layer and allowing passage of ink to a transversely located position upon the layer, which transversely located position aligns with a slot formed through an adjacent layer.
Preferably the slot in any layer of the structure is aligned with another slot in an adjacent layer of the structure and the aligned slots are aligned with a respective print chip slot formed in a final layer of the structure.
Preferably the layers are micro-molded plastics layers.
The present invention also provides a method of distributing ink to an array of print chips in a printhead assembly, the method serving to distribute different inks from respective ink sources to each said print chip for printing on a sheet, the method comprising:
supplying individual sources of ink to a longitudinal distribution molding having a duct for each said different ink extending longitudinally therealong,
causing ink to pass along the individual ducts for distribution thereby into a laminated ink distribution structure fixed to the distribution housing, wherein
the laminated ink distribution structure enables the passage therethrough of the individual ink supplies to the print chips, which print chips selectively eject the ink onto a sheet.
The present invention also provides a method of distributing ink to print chips in a printhead assembly of a printer, the method utilizing a laminated ink distributing structure formed as a number of micro-molded layers adhered to one another with each layer including a plurality of ink holes formed therethrough, each ink hole communicating with a channel formed in one side of a said layer and allowing passage of ink to a transversely located position within the structure, which transversely located position aligns with an aperture formed through an adjacent layer of the laminated structure, an adjacent layer or layers of the laminated structure also including slots through which ink passes to the print chips.
As used herein, the term xe2x80x9cinkxe2x80x9d is intended to mean any fluid which flows through the printhead to be delivered to a sheet. The fluid may be one of many different coloured inks, infra-red ink, a fixative or the like.